Locking mechanisms for office furniture items have become very popular in recent years due to the confidential or private nature of information kept in many offices. As a result, office furniture such as for example, filing cabinets, credenzas and desks are commonly built with key locks so that drawers may be locked to prevent unauthorized persons from accessing sensitive documents. These locking mechanisms have previously been built into a housing which is received into an opening formed in a drawer. Standard locking mechanisms include a driver which is rotated by a key to rotate a separate tenon. The tenon is coupled to a latch whereby the rotation of the tenon is translated to movement of the latch between locked and unlocked positions. These locking mechanisms are provided with a detent in order to provide discrete locked and unlocked positions. A spring and ball type detent mechanism is most commonly used. The spring is built into the driver portion of the locking mechanism. This arrangement requires the tenon and the driver portions of the locking mechanism to be inserted into opposite sides of the locking core housing. The driver and the tenon are then joined together mechanically. Most commonly, these portions are joined together by riveting, screws, nuts or other fasteners. This arrangement may also require the use of an O-ring to firmly secure the moving parts in rotational engagement with the locking core housing.
The prior art systems have the disadvantage of requiring separately machined tenon and driver components. This results in elevated manufacturing costs and assembly time. These systems are also prone to failure, in part, because the tenon and driver must be securely riveted or screwed together in proper alignment relative to each other and to the housing. For example, the repetitive snapping or jarring action of the detent over extended periods of operation may cause the screw to pop out resulting in separation of the tenon and driver, leading to mechanical failure of the part.
Prior art locking mechanisms also require the housing to be fastened to a retaining plate by means of a discrete, rearward mounted retainer clip. This arrangement requires an installer to climb behind the furniture item and to install the retainer clip. This is very inconvenient and leads to elevated costs due to increased labour time. Installation errors may also occur where the retainer clip is installed improperly.
There is therefore a need for a locking mechanism for storage containers including office furniture drawers wherein the driver and the tenon can be machined as a single piece. This unitary construction will avoid many of the problems associated with the prior art systems. Production costs are likely to decline and a locking system will result that are less prone to failure.